public async Task CloseConnectionAsync(IConnectionContext connection)
{
Connections.TryRemove(connection.ConnectionId, out var _);
await _messagingProtocolHandler.HandleConnectionClosed(
new OperationMessageContext(connection.ConnectionId,
connection.Writer, new OperationMessage
{
Type = MessageTypes.GQL_CONNECTION_TERMINATE
})).ConfigureAwait(false);
await connection.CloseAsync().ConfigureAwait(false);
}